ILM was called in late in the 'Avatar' development process to help finish a series of the movie's shots.
(Credit: Industrial Light & Magic)Update (11:49 a.m.): Weta Digital has been contacted for comment, and this story will be updated when and if the company responds.
SAN FRANCISCO--About a year ago, with James Cameron's science-fiction epic "Avatar" well under way, it became clear that Weta Digital, the visual effects studio doing much of the computer generated imagery, or CGI, on the project, was a bit in over its head.
At that point, the movie, which opened Friday, was about 40 minutes longer than it ended up being, and what was needed to finish the project was another company that could come in and lend a helping hand--and do so at the same, very high level, that Weta was working at.
And that's where Industrial Light & Magic came in, recalled John Knoll, the Oscar-winning visual effects supervisor tasked with parachuting in to help finish what was, more than on most films, the crucial job of crafting the "Avatar" CGI work.
What followed was months of coordination between ILM, Weta, and Cameron's production company, Lightstorm Entertainment, with a primary goal of ensuring that the two visual effects teams, one in San Francisco and the other in New Zealand, avoided any unnecessary duplication of effort, even as both sometimes found themselves working on effects for the same movie sequences.
For ILM, this wasn't the first time it had been called in to help aid another effects house, but it may well have been the first time it did so for one as big and as accomplished as Weta. To be sure, ILM's overall contribution to the finished film was minor compared to Weta's, but nonetheless critical in helping get the film to its final, finished state, Knoll suggested.
For Knoll, the challenge of working alongside Weta was about identifying a body of work that limited the number of assets the ILM team had to develop and which would allow them to be the most helpful. Ultimately, they were handed the keys to creating the visual effects for many of the specialized vehicles in the film, including the Valkyrie, a large shuttle used to move people and equipment, and several different types of helicopters, as well as the landscapes those vehicles lived in.
ILM was mostly given responsibility for doing the visual effects on the film's aircraft, notably its helicopters and the Valkyrie, a large-scale shuttle.
(Credit: Industrial Light & Magic)ILM also did the effects work on the film's final battle scene, taking responsibility for the shots of all the vehicles taking off, as well as the sequence's cockpit interior shots.
Working together on a scene
For the most part, the teams at ILM and Weta worked on different scenes, but Knoll said there were some in which the two companies handles different parts of the same sequence. An example, he said, was a scene in the film where a group of helicopters attack the giant "home tree," where the Navi, the humanoid alien race in the film, live. Knoll said that the effects in the scene were mainly put together by Weta, but ILM handled all the shots in which the camera looks back toward the choppers.
In the scenes where the two effects houses both were charged with creating shots, the challenge was figuring out how to "checkerboard" the shots, Knoll said, especially because in some cases, ILM didn't know what Weta's work looked like.
"You keep cutting back between ILM shots and Weta shots," Knoll said. "They're really intermixed. I was worried, because we had to get going and go pretty far down the line before we had any Weta shots to refer to. We were both doing development in parallel."
This might have been a serious problem on many film projects, but with "Avatar," both ILM and Weta were working from extremely detailed templates given to them by Cameron. Knoll said that the templates gave his team very specific direction on how they should construct their shots, down to rough indications of the lighting in the scenes.
"It did help that the templates were so specific," Knoll said. "They were very detailed and Jim [Cameron] was very insistent: 'I've put a lot of time into making sure these are exactly what I want them to be, so you need to do a good job of matching that.'"
Still, with both houses working in parallel, there was certainly a bit of a race to finish a shot, Knoll said, because the team that was fastest would be able to more or less set the tone for the whole scene. "Whoever gets there first is who drives it," he said.
ILM visual effects supervisor John Knoll hopes that audiences won't be able to tell the difference between shots created by Industrial Light & Magic and those created by the film's original visual effects house, Weta Digital.
(Credit: Weta)"For example, in the home tree sequence, we have to fire a bunch of missiles," Knoll recalled. "[There wasn't] anything established for what the missile trails look like. We did our own version of the what [they] would look like and Jim liked it, so that's what Weta had to match."
Of course, in other cases, Weta would finish first, and ILM would have to match what the New Zealanders came up with. And in some cases, it was a bit of "splitting the difference," Knoll said. Ultimately, he added, he hopes that audience members won't be able to tell that two separate visual effects teams shared the work.
All-CGI explosions
One benefit for the entire film industry of having ILM step in to help out on "Avatar" may be that in working on the project, Knoll and his team came up with a new way to completely computer-generate large-scale, close-up explosions.
Until now, big fiery explosions in CGI-heavy films have been shot with live camera and then had visual effects added to them. But Knoll said that because of some of the limitation of matching Cameron's templates for "Avatar," there was no practical way to meet the movie's explosive needs with live-action.
"We've done CG explosions in the past," Knoll said, "but never with this level of realism, and never this close up."
Fortunately, ILM had pioneered the rendering of the visual movement of fluids in films like "Poseidon" and "Pirates of the Caribbean," and Knoll knew that the shape and movement dynamics of an explosion were similar to that of water.
"The same underlying engine is being used on this," Knoll said. "The motion of the underlying gas is similar to the motion of fluids. The medium is relatively uncompressable. So when there's movement of the medium, it can't change volume real dramatically. So if you push on one side, something has to push on the other side."
That meant that ILM could take the graphics engine it had created for fluid shots in the previous films and apply the same basic technology for the explosions in "Avatar." Though there are clearly some major differences between fluid and big fire--notably that as fuel burns, fire expands, and then retracts when the fuel goes away, the technique was similar enough that the technology could be adapted to the needs of "Avatar."
"I think this is going to be an important technique (for the industry) in the future," Knoll said, "to tailor-make an explosion that looks good close up."
The fifth paragraph in this story was updated on December 22 to better reflect Knoll's statements of how and when ILM came to be involved in "Avatar" and what the company's impact on it was.
Spoiler alert: This article describes some of the action sequences in the new Terminator movie. If you don't want to know details about some scenes, bookmark this article and come back to read it after you've seen the movie.
In 'Terminator Salvation,' visual effects and computer graphics played a big part in making many of the action sequences look realistic. This is a mototerminator, a key evil robot in the film, and one that required the visual effects team at ILM to work hard on making an exploding car do what they wanted.
(Credit: Daniel Terdiman/CNET; and image copyright 2009 Warner Bros. Courtesy of Industrial Light & Magic)SAN FRANCISCO--What do you do if you're a filmmaker trying to capture a scene in which an onrushing tow truck slams into a parked car, sending the car rolling neatly up and over the truck's back, but you face the reality that the car, vaulted into the air by a cannon shot from below, actually flies high above the truck?
If you're making "Terminator Salvation," or T4 as it's known, the latest salvo in the 25-year-old series, you turn to the visual effects experts at Industrial Light & Magic and depend on them to solve the problem.
And solve it they did. Those who see the film, which opened Friday, will see the collision rocket the car into the air and, indeed, roll right over the back of the tow truck. They'll never know that in real-life, the car actually soared high and straight up into the air.
Why did it matter? According to Ben Snow, the ILM visual effects supervisor on T4--who had the same title on films like "King Kong" and "Iron Man"--it had every bit to do with the film's story. In the scene, the driver of the tow truck is trying to derail a so-called mototerminator, a high-speed killer robot in the body of a super motorcycle that is chasing fast behind. But the mototerminator is an intelligent machine, and isn't so easily knocked down.
So, Snow said, the point of the exploding car is that it's supposed to fall over the top of the truck and into the mototerminator's path, providing the evil robot the chance to showcase its instant maneuvering skills. And to turn that high-flying car into something that looks, on-screen, just as the script called for required a whole lot of visual effects.
"Usually we try and do it" for real, Snow said, "but it would be a miracle with an effect like this. So you weigh if it's worth standing around with an expensive film crew for a day trying to get it. Do we have more than one go at it?"
Instead, Snow explained, the real-life footage of the car exploding into the air was enough for the visual effects team to get going on the computer graphics (CG) version of the sequence. They combined the real footage with a digital version of the car that was based on some still photos they'd taken, and then they simulated the desired rolling-over-the-truck effect using ILM's proprietary rigid body simulation tools in order to produce the CG version.
Snow said that the footage of the truck, taken from behind, was doctored with visual effects to show it from the point of view of the mototerminator, which has a heads-up display calculating what's happening with the car.
"The story point," Snow said, "is that this mototerminator is reacting to the car, and able to do an incredibly nimble evasive maneuver to get out of the way. So we're trying to tell the story of these things being really bad-ass."
In the past, a movie studio might still have tried to produce a similar effect but Snow said that filmmakers might well have been less likely to turn to CG for the effect.
"I think we would have tried a lot harder to get the effect for real with the car," he said. "I can now depend on effects. I can take existing material and re-project it and get it to do what I need to...I can count on the fact that I can get a believable rigid-body simulation of something like a crumpling, rolling car. I mean, we were doing those kinds of things (a few years ago) on "Twister" and "Star Wars." But if you compare the realism of what we're able to achieve now to what we were able to achieve five years ago, it's way more realistic now."
That sort of advance, Snow continued, means that Warner Bros. and director McG can "make a Terminator for the 21st century...updated to give it a more gritty, edgy feel. Instead a guy puppeteering the robot, we're able to have the robot running around and chasing people."
Explosions on a bridge
Another of T4's major action sequences involves a large-scale battle that includes several forceful explosions on a bridge high over a river gorge. But Snow said that since it was obvious that the filmmakers couldn't conduct the explosions on the actual bridge--the fantastic Rio Grande Gorge Bridge near Taos, N.M.--it was necessary to film the sequence in three different places and then blend the footage together using visual effects and CG.
The sequence was shot on the bridge, on a nearby roadway and on a set on a field in Albuquerque, N.M., where they could actually blow up a truck.
Creating this action sequence required shooting at three different locations in order to make a truck explode on the bridge, something that the filmmakers could not do in real life. Then, it was up to the visual effects team at ILM to stitch it all together using newly-developed CG techniques.
(Credit: Image copyright 2009 Warner Bros. Courtesy of Industrial Light & Magic)The sequence, then, involves combining footage from the three different locations, going back and forth between them depending on the severity of destruction in each frame, and using CG to patch them together seamlessly.
Snow explained that putting the sequence together meant marrying footage from all three locations, adding digital backgrounds when needed, adding railings to the CG bridge, and adding the CG truck to the bridge.
"We re-projected this onto the (CG bridge) so I could have the truck fall over the edge, because in the original, it didn't fall over the edge," Snow said. And "those sort of techniques are just some of the things that we've been perfecting over the years: re-projection, the ability to say, 'Well, we can go and do this, shoot at three different locations, and we don't always have to use blue screen.' ...We can make it so you don't know which bit of the bridge is CG."
And, importantly, it means that for the filmmakers, there's no worrying about whether they can fulfill the all-important script element of blowing up a truck on a bridge.
Molten metal
For Snow's visual effects teams, the hardest part of working on T4 was getting the film's molten metal sequence just right. This meant making a scene in which melted metal pours through a terminator look believable, even though it's done in CG.
"We have some very good fluid simulation tools that we've developed over the years," Snow said, "but getting the molten metal to pour in and through this skeletal robot and look believable involved a lot more computing power than we've (ever used before). That was surprisingly hard, given that in the end, it's only in a few shots." It's funny seeing the film now, Snow said, because it's over in seconds and took days and more than a hundred high-power processors to create.
By comparison, Snow said, previous fluid sequences in films like "Pearl Harbor" used 30 lower-power processors and were considered beyond state-of-the-art at the time.
Today, visual effects teams like those at ILM still struggle to do realistic digital doubles and CG fire, Snow said, but the barriers to such effects are breaking down rapidly. And that could mean that in the near future, filmmakers can turn to CG to get just about any effect they want.
"The sky is the limit with digital technology," Snow said. "We're not limited by physical constraint. And so there's no time for complacency."
On June 22, Geek Gestalt will kick off Road Trip 2009. After driving more than 12,000 miles in the Pacific Northwest, the Southwest and the Southeast over the last three years, I'll be looking for the best in technology, science, military, nature, aviation and more in Colorado, Utah, Idaho, Wyoming, Montana and South and North Dakota. If you have a suggestion for someplace to visit, drop me a line. And in the meantime, join the Road Trip 2009 Facebook page and follow my Twitter feed.
While wearing a motion-capture suit, CNET reporter Kara Tsuboi shows how her movements are translated instantly to an 'Iron Man' character on the screen behind her. The technique is used in an increasing number of films to mix live-action footage with digital, 3D sets.
(Credit: Daniel Terdiman/CNET News)SAN FRANCISCO--On Tuesday, the DVD version of the mega-hit film Iron Man will be released, and to celebrate, the visual effects superstars at Industrial Light & Magic decided to show off just a little bit more magic behind the movie.
Back in April, ILM invited me and a couple of my colleagues to their fantastic facilities here for a look at the technology behind the famous suit used in Iron Man. Recently, they invited us back to see how the seamless animation in some of the film's scenes--such as one famous shot involving the throwing of an Audi--was produced.
In particular, they wanted to give us the inside scoop on the motion-capture technology used to create a number of the film's scenes, a technology that is increasingly being used today that allows directors to see, in real time, while the actors are acting, what animated sequences will look like.
That's why we--myself, CNET reporter Kara Tsuboi, and a cameraman--spent several hours on an ILM image capture stage last week: So that Tsuboi could don a motion-capture suit and we could all see how footage of her would translate instantly into an animated Iron Man scene.
The idea is that George Lucas--who owns the effects studio--wants to give filmmakers advanced technological tools that provide them with flexibility and efficiency. And so he staffs ILM with the kinds of people who can make that happen.
"We understand the entire process," said , "from writing code to animating creatures to even shooting live elements. So we know each layer in the process. We understand the vision of the key creatives and understand" what the actors are going to do.
The technology used at ILM--and elsewhere, as well--allows directors to mix real filmmaking and virtual spaces, but with full camera control, depth of field, tracking, and panning. The upshot? A filmmaker can have an entire digital set created, then have an actor perform on the image capture stage wearing the motion-capture suit, and see, as the filming is happening, how the actor's character looks superimposed on the digital background.
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